Terminal devices, which come into contact with a human body (such as the hand or the head) when in use, are governed by safety regulations which stipulate the allowable degree of negative effects of electromagnetic waves on the human body. However, terminal devices capable of wireless communication are expected to be effective in providing wireless communication. Hence, both human body safety and wireless communication capability must be taken into account.
In general, a conventional proximity sensing device is deemed a solution to the aforesaid issue. The proximity sensing device is designed to sense whether a human body is approaching the terminal device and thus generate a corresponding sensing message. Therefore, when the proximity sensing device senses that a human body is approaching (or in contact with) the terminal device, a control circuit changes the present operating mode of a wireless unit and thereby alters electromagnetic radiation, with a view to complying with the safety regulations. By contrast, when the proximity sensing device senses that no human body is approaching (or in contact with) the terminal device, the terminal device is switched to the operating mode most favorable to wireless communication.